The TDP-1 Mono Passive Direct Box combines premium quality components with robust construction to create a reliable DI with rich, warm tone and character.

While some direct boxes focus on providing sterile, ultra-clean gain, they often leave the instrument devoid of any soul or character. Conversely, some DI’s artificially hype too much low-end and over emphasize harmonic distortion, resulting in a tubby and undefined output. The Telefunken passive DI avoids these common design pitfalls and delivers a new standard in reliability and performance for direct boxes.

The heart of the design is a custom-wound output transformer by OEP/Carnhill, made in the UK. The circuit board features gold plated traces and is entirely hand-assembled with through-hole components, providing more secure and reliable connections than typical surface mount circuitry. The frequency response of the circuit is ± 1dB from 10 Hz to 70 kHz, with extremely low distortion and self-noise. Each individual unit is manually tuned by hand for the lowest distortion figure possible. High input impedance prevents the loading down of passive pickups. This careful attention to detail and high quality component choices results in a direct box with a harmonically rich low end and a detailed, open high-end clarity.

The circuit is housed in an extremely durable extruded aluminum enclosure with recessed switches and connectors. This rugged construction is virtually indestructible, able to easily withstand the wear and tear of gigging. Each channel features two heavy duty metal toggle switches to engage a -15 dB pad and ground lift.

The Features
- Custom-wound OEP/Carnhill transformer, made in the UK
- -15 dB pad switch
- Ground lift switch
- Rugged aluminum construction
- Recessed switches and connectors for protection
- 100% through-hole components
- Amphenol connectors
- WIMA and Nichicon capacitors•
1% 1/4W metal film resistors
- 3-year warranty